What I want to know is how they guess which 0.001% of signals or internet traffic is actually worthwhile to keep? The biggest nation states could conceivably store about 1 year’s worth of internet traffic right now, but then they also need to store whatever other signals intelligence they’re gathering for analysis, so it will be less than a single years worth.

But almost all that data is going to turn out to be useless if or when they gain quantum ability to decrypt it, and even the stuff that could be useful now gets less useful with every month it stays encrypted. Stuff that is very useful intelligence now could be absolutely useless in five years…